The central nervous system is a vital part of the human physiology that coordinates human activity. It is primarily made up of the brain and the spinal chord, with the spinal chord acting as a conduit to communicate neuronal signals from the brain to the rest of the body, including motor control and sensations. Protecting the spinal chord is the spinal, or vertebral, column. While most people have fully functional spinal chords, it is not uncommon for individuals to suffer some type of spinal ailment, including spondylolisthesis, scoliosis, or spinal fractures. In severe cases where non-surgical procedures are not effective, or for cases which have developed into spinal instability or severe disc degeneration, surgical intervention may be required.
There are many different approaches taken to alleviate or minimize severe spinal disorders. One surgical procedure commonly used is a spinal fusion technique. Spinal fusion is a standard back surgical technique and its use continues to rise. In addition to the spinal implants or use of bone grafts, spinal fusion surgery often utilizes spinal instrumentation or surgical hardware, such as pedicle screws, plates, or spinal rods. Once the spinal spacers and/or bone grafts have been inserted, a surgeon places the pedicle screws into a portion of the spinal vertebrae and attaches either rods or plates to the screws as a means for stabilization while the bones fuse.
While spinal fixation procedures can have positive outcomes, adjacent segment degeneration (ASD) often follows fusion surgeries. In addition to requiring the fusion of additional spinal segments, patients suffering from ASD often require posterior pedicle screw rod fixation. Such cases can be difficult for the surgeon as the surgical procedure often requires “opening” of the patient's back to expose the entire system in order for the surgeon to get to the top tulip. Such procedure is not beneficial to the patient as it exposes them to increased pain, higher morbidity, worsening of paraspinal muscle fibrosis/atrophy. Should the surgeon need to completely remove the old system, trying to remove an existing rod in order to provide a new construct can be technically difficult. Moreover, given the number of different spinal fixation systems in the market, knowing what system the patient contains and having he right tools to work on that system is a challenge.
There exists, therefore, a need for an improved devices and systems for extending a patient's existing fixation hardware which does not require open dissection, reduces the disruption of post tension bands, and can be used with any existing pedicle screw system in place.